Implications and challenges of connexin connections to cancer

Christian C Naus1, Dale W Laird

  • 1Life Sciences Institute, Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia V6T-1Z3, Canada. Christian.naus@ubc.ca

Insights

Connexins, proteins forming gap junctions, were thought to universally suppress tumors. However, new evidence shows they can also promote cancer progression, suggesting connexins act as conditional tumor suppressors.

Area of Science:

  • Cell Biology
  • Molecular Oncology
  • Cancer Research

Background:

  • Gap junction proteins, known as connexins, have been widely regarded as tumor suppressors in various cancer models.
  • This perspective suggested that enhanced gap junctional intercellular communication universally restricts tumor growth.

Purpose of the Study:

  • To re-evaluate the role of connexins in cancer, challenging the established paradigm.
  • To investigate the dual function of connexins in tumor suppression and progression.

Main Methods:

  • Review of existing cancer models and recent experimental evidence.
  • Analysis of studies investigating connexin function in cell proliferation, adhesion, and migration.

Main Results:

  • Recent evidence indicates connexins can facilitate tumor progression and metastasis, contradicting their universal suppressor role.
  • Connexins' function appears context-dependent, influencing various cancer hallmarks.

Conclusions:

  • Connexins may be better classified as conditional tumor suppressors.
  • Their role in cancer is complex, modulating cell proliferation, adhesion, and migration based on the cellular context.

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